Double-blind, randomized, controlled trial of zinc or vitamin A supplementation in young children with acute diarrhoea

In a double-blind, controlled trial with a factorial design, 684 patients (aged 6 months to 2 y; excludes 6 early dropouts) with acute watery diarrhoea of 3 d or less and some dehydration, who were attending a hospital, were randomly assigned to 4 groups to receive: (a) vitamin A 4500 microg retinol equivalent daily for 15 d; (b) 14.2 mg elemental zinc as acetate for the first 417 patients and 40 mg of the remaining 273 patients randomized to this group for 15 d; (c) both vitamin A 4500 microg retinol equivalent and zinc at the above doses daily for 15 d; or (d) placebo mixtures for 15 d. Patients were observed in the hospital for 24 h and followed up at home for 15 d. All received ascorbic acid 30 mg with each dose of medicine or placebo. Zinc supplementation was associated with a reduced duration of diarrhoea (13%, p = 0.03) and markedly reduced rate (43%, p = 0.017) of prolonged diarrhoea (>7 d). Vitamin A supplementation was associated with a nonsignificant trend for reduced rate of prolonged diarrhoea (p = 0.089). In conclusion, zinc supplementation as adjunct therapy had a substantial impact on the rate of prolonged diarrhoea and some impact on duration and may be beneficial in children with diarrhoea in developing countries.